In the operation of superconducting magnets for use in magnetohydrodynamic (MHD) and plasma devices, superconductors are utilized to provide the required high electrical currents. Commonly, the superconductors are constructed of one or more layers of a superconductor such as a niobium compound and a conventional conductor such as copper. The presence of the copper conductor provides a current carrying capacity if the superconductor is switched to its resistance mode by the field or temperature exceeding the critical values.
To avoid the switching between the superconducting and resistance modes for the superconductor, it is important that the critical values of field (H.sub.c) and/or temperature (T.sub.c) be as large as possible to tolerate variations in operating conditions of superconducting magnets. Also with respect to critical field values, improvements in this factor may permit more efficient designs of the magnets.
Accordingly, one object of this invention is a superconductor having an improved value of critical field. Another object of the invention is a superconductor for a superconducting magnet with the superconductor having ductility for forming coils. These and other objects will become apparent from the detailed description.